The government is planning to offer a "health MoT" - a medical check-up free on the NHS - to everyone who retires, as part of its strategy to identify potential illnesses before they become serious.

The change, which is designed to help poorer people who are more likely to need it, will consist of a visit to the GP or practice nurse where basic conditions such as blood pressure, heartbeat, lungs and breathing can be examined.

But, unlike the mass health check-ups that were a feature of life in the former Soviet Union, the new service - described as a "health MoT" by Alan Milburn, the health secretary - will be voluntary, to avoid accusations of "nanny state" interference.

It means that, whether people retire at 50, 60 or 65, they will be entitled to a check-up without paying for it privately or through insurance.

Ministers have acted after learning that free eye tests - restored by Labour in 1999 - have produced a 2.5m (33%) increase in tests as older people with poor eyesight have come forward.

Tony Blair will announce the health service's own MoT test on July 26 as part of the prevention-oriented national plan for health that Downing Street, the Treasury and the Department of Health have been devising since the prime minister signalled a doubling of the annual increase in NHS spending - from 3% to 6% - in January.

It should produce a cumulative 30% increase in real terms by 2004 as part of the second comprehensive spending review by Gordon Brown, the chancellor, which is due next Tuesday. Transport and health are the key elements.

The thrust of the health plan rests heavily on prevention and early intervention to stop people getting seriously ill - in contrast to past advertising campaigns urging them to adopt a healthier lifestyle.

Unlike some of the government's initiatives such as the NHS Direct hotline, which has been criticised for not being properly tested, the new scheme will have pilot schemes in needier areas next spring.

NHS walk-in clinics and healthy living centres, both Labour innovations, may be used for the trials.

The reform will cost the NHS budget millions and may add to the demands made on hard-pressed GPs, but is part of Mr Milburn's drive to make the health service more consumer-sensitive and restore public confidence.

The health secretary has told his colleagues: "I would like everyone to have the opportunity of a retirement medical free on the NHS, not just those lucky enough to have a generous employer or have paid medical insurance. People should be able to enjoy a happy and healthy retirement."

With earlier screening of such conditions as high blood pressure or cataracts, "we can make earlier interventions and nip them in the bud", Mr Milburn said.